1. Field of the Invention
The present invention relates to an imprint apparatus for pressing resin on a shot region of a substrate and a mold to each other to form a resin pattern on the shot region.
2. Description of the Related Art
There is known nanoimprinting, which is a technique replacing a method of forming fine patterns of semiconductor devices and micro electro-mechanical systems (MEMS) by photolithography using ultraviolet rays, X-rays, and electron beams. In the nanoimprinting, a mold (also referred to as a “template or original”) having fine patterns formed by exposure with an electron beam is pressed against (imprinted onto) a substrate, such as a wafer, coated with a resin material to transfer the patterns to the resin.
There are several types of nanoimprinting, and one of those is a photo-curing method (U.S. Pat. No. 7,027,156). In the photo-curing method, a transparent mold is pressed against a UV-curable resin, and the mold is separated (released) after the resin is exposed and cured. The nanoimprinting using the photo-curing method is suitable for the manufacture of semiconductor integrated circuits because the temperature control is relatively easy and an alignment mark on the substrate can be observed through the transparent mold.
Although there is a method in which a pattern is transferred to the entire surface of the substrate at a time, taking into consideration the case where different patterns are superposed, it is desirable to employ a step-and-repeat method, in which a mold having substantially the same size as the chip of the device to be manufactured is fabricated and the pattern thereon is successively transferred to the shot regions on the substrate.
In addition, it is desirable to use a suitable one of a die-by-die method, in which the alignment is performed on each shot region, and a global alignment method, depending on the alignment accuracy of the shot regions and the throughput.
In conventional semiconductor exposure apparatuses, the time for measuring the sample shot regions during global alignment is a problem from the standpoint of throughput.
To overcome the above-described problem, Japanese Patent Laid-Open No. 2007-184342 discloses a method in which a stage for measurement is prepared separately from the substrate stage for exposure that carries the substrate, and in which a plurality of alignment measurement devices simultaneously measure the sample shot regions on the substrate in an off-axis manner. Although this method can reduce the time for measurement because the substrate stage does not move when the sample shot regions are measured, a stage for measurement needs to be prepared separately from the substrate stage for exposure and a substrate conveying unit has to be installed between the stages. If, instead, the substrate stage for exposure that carries the substrate is moved to a position of the alignment measurement devices to measure the sample shot regions, the footprint of the exposure apparatus increases, resulting in a problem in that the entire apparatus becomes large.
On the other hand, in nanoimprinting apparatuses, a dispenser head for discharging UV-curable resin is usually disposed near a mold holding unit from the standpoint of the required stroke length of the substrate stage. Therefore, if both die-by-die alignment and the global alignment are to be performed, it is difficult to secure a space for an off-axis alignment scope for measuring the sample shot regions used in the global alignment. Depending on the position of the off-axis alignment scope, the stroke length of the substrate stage added to measure the sample shot regions may become too large, or the throughput of the apparatus may be reduced.